As if losing your job when the startup you work for goes bankrupt isn't bad enough, security researchers have found that employees of failed startups are especially at risk of having their data stolen. This can range from personal Slack messages to social security numbers and even bank accounts.
The researcher who discovered the issue is Dylan Ailey, co-founder and CEO of Truffle Security, a startup backed by Andreessen Horowitz. Ayrey is best known as the creator of the popular open source project TruffleHog. TruffleHog helps you monitor data leaks if bad actors obtain your identity login tools (API keys, passwords, tokens).
Ayrey is also a rising star in the world of bug hunting. At last week's security conference ShmooCon, he spoke about flaws he discovered in Google OAuth, the technology behind the “Sign in with Google” password replacement.
Ayrey gave the talk after reporting the vulnerability to Google and other potentially affected companies, and said he was not allowed to share details since Google does not prohibit telling bug hunters about their findings. is completed. (For example, Google's 10-year-old Project Zero frequently showcases flaws found in products from other major technology companies, such as Microsoft Windows.)
He says that if a malicious hacker buys a defunct domain from a failed startup, they can use that domain to create cloud software that is set up to be accessible to all employees at the company, including internal chat and video apps. I discovered that it is possible to log into . Many of these apps offer company directories and user information pages from which hackers can discover former employees' real emails.
Armed with domains and their emails, hackers can use the “Sign in with Google” option to access the startup's many cloud software apps and often discover more employee emails. There is a gender.
To test the flaws he discovered, Ayrey purchased the failed startup's domain, from which he could log into ChatGPT, Slack, Notion, Zoom, and human resources systems, including Social Security numbers. .
“That's probably the biggest threat,” Iley told TechCrunch. Data from cloud HR systems is “the easiest to monetize, and social security numbers, banking information, and anything else in HR systems is probably the most likely to be stolen.” He said, and Google confirmed that, no data created by employees in old Gmail accounts, Google Docs or Google apps was at risk.
Any failed company that puts a domain up for sale is potential prey, but since startups tend to use Google apps and a lot of cloud software to run their business, startups' employees employees are particularly vulnerable.
Ayrey calculates that tens of thousands of former employees are at risk, as well as millions of SaaS software accounts. This is based on his research, which found that 116,000 website domains are currently for sale from failed technology startups.
Prevention is possible but not perfect
In fact, Google's OAuth configuration includes techniques that prevent the risks outlined by Ayrey when used by SaaS cloud providers. This is called a “sub-identifier” and is a series of numbers that are unique to each Google Account. Employees may have multiple email addresses associated with their work Google Account, but only one account needs to include a sub-identifier.
If configured, when an employee attempts to log in to a cloud software account using OAuth, Google sends both the email address and a sub-identifier to identify the individual. Therefore, even if a malicious hacker were to take control of your domain and recreate your email addresses, they should not be able to recreate these identifiers.
However, Ayrey, who was working with one of the affected SaaS HR providers, found this identifier to be “unreliable.” In other words, HR providers found that a very small percentage (0.04%) of their identifiers changed. This may be statistically close to zero, but for HR providers that handle huge numbers of users every day, this can add up to hundreds of failed logins each week, locking people out of their accounts. That's it. That's why the cloud provider didn't want to use Google's sub-identifiers, Ailey said.
Google objects to sub-identifiers changing. Because this finding came from the HR cloud provider rather than researchers, it was not submitted to Google as part of a bug report. Google has said that if it finds evidence that a sub-identifier is untrustworthy, the company will address it.
Google changes its mind
But Google has also upended just how important this issue is. Initially, Google completely ignored Ayrey's bug, quickly closing the ticket and saying it was a “fraud” issue rather than a bug. Google wasn't completely wrong. This risk arises from hackers taking control of a domain and exploiting email accounts recreated from it. Ayrey expressed no regrets about Google's initial decision, saying it was a data privacy issue where Google's OAuth software worked as intended despite the potential harm to users. I called. “It's not that simple,” he said.
But three months later, shortly after his talk was accepted at ShmooCon, Google changed its mind, reopened the ticket, and paid Ayrey $1,337 in compensation. Something similar happened to him in 2021 when Google reissued him a ticket after he gave a highly popular talk about his findings at the Black Hat cybersecurity conference. Google awarded Ayrey and his bug-finding partner Allison Donovan the third award of its annual Security Researcher Award (and $73,331).
Google has not yet announced a technical fix for this flaw, nor has it announced a timeline for when the fix will occur. It's also not clear whether Google will make any technical changes to address this issue in any way. However, the company has updated its documentation to direct cloud providers to use sub-identifiers. Google is also instructing founders on how companies can properly shut down Google Workspace to avoid problems.
Ultimately, Google says the solution is to allow founders who shut down their companies to gracefully shut down all of their cloud services. “We would like to thank Dylan Ayrey for his assistance in helping us identify the risks posed by customers forgetting to remove third-party SaaS services as part of their refusal to operate them,” the spokesperson said.
As a founder himself, Ayrey understands why many founders haven't been able to reliably disable cloud services. Closing down a company is actually a complex process that takes place during a potentially emotionally distressing time, with many challenges ranging from disposing of employee computers to closing bank accounts to paying taxes. Contains items.
“When a founder has to deal with a company closing, they probably don't have the mental space to think about all the things they have to think about,” Eyley says.